Auditing a large legacy billing system

Andrew Hume

                      AT&T Labs -- Research
Auditing telecom billing is normally done by analyzing statistical summaries of each system within the billing chain and, in some cases, by tracking very small sets of calls throughout the billing chain. This talk describes Gecko, a system for tracking *every* call throughout the entire billing chain. The talk will cover why this system can't possibly be done (at least that's what they said) and how we were able to implement it. As an example of the difficulties, we note that a small prototype version that tracked calls made on three days processed over 4.5TB of data.